If I have a 2 string array, can I splice the 2 strings together to an appropriate sized feed conductor and then terminate to the combiner panel ,or does each string have to be individually run to the combiner?

Example:

String NEC x1.56= 10ampsArray NEC x1.56= 20amps

Wirenut the 2 strings to a #8 (sized for line loss) and land on 20a combiner breaker. Permitted by NEC or not.